Figure 4.

AvrBs2_Xhc and XopQ_Xhc elicit a hypersensitive response in tobacco plants. Plants were challenged with optical density at 600 nm (OD₆₀₀) = 1.0 of Agrobacterium tumefaciens carrying avrBs2, xopQ or hopQ1‐1 under the regulation of the cauliflower mosaic virus (CaMV) 35S promoter. (a) Wild‐type and transgenic Nicotiana benthamiana, expressing Bs2, were challenged with A. tumefaciens carrying avrBs2 (Tai et al., 1999). (b) Wild‐type N. tabacum was challenged with A. tumefaciens carrying xopQ or hopQ1‐1. Twenty‐four leaf panels were infiltrated per experiment and experiments were repeated three times with identical results (percentages with a response are shown). Plant responses were scored 24 h post‐infection.